Category: Academic Analysis

Source: The Conversation – USA – By Mojtaba Akhavan-Tafti, Associate Research Scientist, University of Michigan

The burgeoning space industry and the technologies society increasingly relies on – electric grids, aviation and telecommunications – are all vulnerable to the same threat: space weather.

Space weather encompasses any variations in the space environment between the Sun and Earth. One common type of space weather event is called an interplanetary coronal mass ejection.

These ejections are bundles of magnetic fields and particles that originate from the Sun. They can travel at speeds up to 1,242 miles per second (2,000 kilometers per second) and may cause geomagnetic storms.

They create beautiful aurora displays – like the northern lights you can sometimes see in the skies – but can also disrupt satellite operations, shut down the electric grid and expose astronauts aboard future crewed missions to the Moon and Mars to lethal doses of radiation.

I’m a heliophysicist and space weather expert, and my team is leading the development of a next-generation satellite constellation called SWIFT, which is designed to predict potentially dangerous space weather events in advance. Our goal is to forecast extreme space weather more accurately and earlier.

The dangers of space weather

Commercial interests now make up a big part of space exploration, focusing on space tourism, building satellite networks, and working toward extracting resources from the Moon and nearby asteroids.

Space is also a critical domain for military operations. Satellites provide essential capabilities for military communication, surveillance, navigation and intelligence.

As countries such as the U.S. grow to depend on infrastructure in space, extreme space weather events pose a greater threat. Today, space weather threatens up to US$2.7 trillion in assets globally.

In September 1859, the most powerful recorded space weather event, known as the Carrington event, caused fires in North America and Europe by supercharging telegraph lines. In August 1972, another Carrington-like event nearly struck the astronauts orbiting the Moon. The radiation dose could have been fatal. More recently, in February 2022, SpaceX lost 39 of its 49 newly launched Starlink satellites because of a moderate space weather event.

Today’s space weather monitors

Space weather services heavily rely on satellites that monitor the solar wind, which is made up of magnetic field lines and particles coming from the Sun, and communicate their observations back to Earth. Scientists can then compare those observations with historical records to predict space weather and explore how the Earth may respond to the observed changes in the solar wind.

Earth’s magnetic field naturally protects living things and Earth-orbiting satellites from most adverse effects of space weather. However, extreme space weather events may compress – or in some cases, peel back – the Earth’s magnetic shield.

This process allows solar wind particles to make it into our protected environment – the magnetosphere – exposing satellites and astronauts onboard space stations to harsh conditions.

Most satellites that continuously monitor Earth-bound space weather orbit relatively close to the planet. Some satellites are positioned in low Earth orbit, about 100 miles (161 kilometers) above Earth’s surface, while others are in geosynchronous orbit, approximately 25,000 miles (40,000 km) away.

At these distances, the satellites remain within Earth’s protective magnetic shield and can reliably measure the planet’s response to space weather conditions. However, to more directly study incoming solar wind, researchers use additional satellites located farther upstream – hundreds of thousands of miles from Earth.

The U.S., the European Space Agency and India all operate space weather monitoring satellites positioned around the L1 Lagrange point – nearly 900,000 miles (1,450,000 km) from Earth – where the gravitational forces of the Sun and Earth balance. From this vantage point, space weather monitors can provide up to 40 minutes of advance warning for incoming solar events.

Advance warning for space weather

Increasing the warning time beyond 40 minutes – the current warning time – would help satellite operators, electric grid planners, flight directors, astronauts and Space Force officers better prepare for extreme space weather events.

For instance, during geomagnetic storms, the atmosphere heats up and expands, increasing drag on satellites in low Earth orbit. With enough advance warning, operators can update their drag calculations to prevent satellites from descending and burning up during these events. With the updated drag calculations, satellite operators could use the satellites’ propulsion systems to maneuver them higher up in orbit.

Airlines could change their routes to avoid exposing passengers and staff to high radiation doses during geomagnetic storms. And future astronauts on the way to or working on the Moon or Mars, which lack protection from these particles, could be alerted in advance to take cover.

Aurora lovers would also appreciate having more time to get to their favorite viewing destinations.

The Space Weather Investigation Frontier

My team and I have been developing a new space weather satellite constellation, named the Space Weather Investigation Frontier. SWIFT will, for the first time, place a space weather monitor beyond the L1 point, at 1.3 million miles (2.1 million kilometers) from Earth. This distance would allow scientists to inform decision-makers of any Earth-bound space weather events up to nearly 60 minutes before arrival.

Satellites with traditional chemical and electric propulsion systems cannot maintain an orbit at that location – farther from Earth and closer to the Sun – for long. This is because they would need to continuously burn fuel to counteract the Sun’s gravitational pull.

To address this issue, our team has spent decades designing and developing a new propulsion system. Our solution is designed to affordably reach a distance that is closer to the Sun than the traditional L1 point, and to operate there reliably for more than a decade by harnessing an abundant and reliable resource – sunlight.

SWIFT would use a fuelless propulsion system called a solar sail to reach its orbit. A solar sail is a hair-thin reflective surface – simulating a very thin mirror – that spans about a third of a football field. It balances the force of light particles coming from the Sun, which pushes it away, with the Sun’s gravity, which pulls it inward.

While a sailboat harnesses the lift created by wind flowing over its curved sails to move across water, a solar sail uses the momentum of photons from sunlight, reflected off its large, shiny sail, to propel a spacecraft through space. Both the sailboat and solar sail exploit the transfer of energy from their respective environments to drive motion without relying on traditional propellants.

A solar sail could enable SWIFT to enter an otherwise unstable sub-L1 orbit without the risk of running out of fuel.

NASA successfully launched its first solar sail in 2010. This in-space demonstration, named NanoSail-D2, featured a 107-square-foot (10 m² ) sail and was placed in low Earth orbit. That same year, the Japanese Space Agency launched a larger solar sail mission, IKAROS, which deployed a 2,110 ft² (196 m² ) sail in the solar wind and successfully orbited Venus.

The Planetary Society and NASA followed up by launching two sails in low Earth orbit: LightSail, with an area of 344 ft² (32 m² ), and the advanced composite solar sail system, with an area of 860 ft² (80 m² ).

The SWIFT team’s solar sail demonstration mission, Solar Cruiser, will be equipped with a much larger sail – it will have area of 17,793 ft² (1,653 m² ) and launch as early as 2029. We successfully deployed a quadrant of the sail on Earth early last year.

To transport it to space, the team will meticulously fold and tightly pack the sail inside a small canister. The biggest challenge to overcome will be deploying the sail once in space and using it to guide the satellite along its orbital path.

If successful, Solar Cruiser will pave the way for SWIFT’s constellation of four satellites. The constellation would include one satellite equipped with sail propulsion, set to be placed in an orbit beyond L1, and three smaller satellites with chemical propulsion in orbit at the L1 Lagrange point.

The satellites will be indefinitely parked at and beyond L1, collecting data in the solar wind without interruption. Each of the four satellites can observe the solar wind from different locations, helping scientists better predict how it may evolve before reaching Earth.

As modern life depends more on space infrastructure, continuing to invest in space weather prediction can protect both space- and ground-based technologies.

Mojtaba Akhavan-Tafti receives funding from NASA. He is the Principal Investigator of Space Weather Investigation Frontier (SWIFT).

– ref. Spacecraft equipped with a solar sail could deliver earlier warnings of space weather threats to Earth’s technologies – https://theconversation.com/spacecraft-equipped-with-a-solar-sail-could-deliver-earlier-warnings-of-space-weather-threats-to-earths-technologies-259877

Source: The Conversation – USA (2) – By Flor Acevedo, Assistant Professor of Entomology, Penn State

Spotted lanternfly season is back in Pennsylvania. The polka-dotted, gray-and-red-winged adult insects make their appearance each July and tend to hang around until December. It’s an unwelcome summer ritual that started in 2014 when the invasive pests were first detected in the U.S.

The Conversation U.S. talked to Flor Acevedo, an assistant professor of entomology at Penn State University, about the bugs and her research on how lanternflies are threatening the state’s vineyards and wine industry.

Does Pennsylvania have many vineyards?

Pennsylvania has more than 400 wineries with about 14,000 acres planted in vineyards, according to the Pennsylvania Wine Association. The industry generates about US$7 billion in total economic activity. Erie County, where I live, has about 70% of Pennsylvania’s vineyard acreage, with the rest scattered across the state.

What do lanternflies do to grapevines?

The spotted lanternfly feeds on many plants, but its preferred hosts are the Tree of Heaven, an invasive plant introduced to Philadelphia from China in 1784, and grapevines.

Extensive feeding by these sap-sucking insects can weaken grapevines and, when combined with other stressors such as diseases or frosty winters, can kill the vines. While spotted lanternflies feed on other important crops such as apple trees, they have been lethal only to grapevines and Tree of Heaven plants.

Feeding can also reduce yield and fruit quality, which affects juice and wine quality.

Tell us about your lanternfly experiments

My lab initially investigated whether spotted lanternflies could survive to adulthood and reproduce when feeding exclusively on grapevines. This would help us determine whether the insects could thrive in regions with extensive grapevine cultivation.

We found they do survive, but their fitness is severely reduced. Insects feeding solely on grapevines had high mortality, slower development and laid fewer eggs when compared with those that had access to a mixed diet of Tree of Heaven and grapevines.

Our next question was whether different grapes would be equally suitable for spotted lanternfly survival and reproduction. In the U.S. we grow native grapevines such as Concord and muscadine as well as vines of European origin. We found that spotted lanternflies did not survive to adulthood when they fed only on muscadine grapevines.

We have also partnered with colleagues specialized in plant science, food science and agricultural economics to investigate the effects of spotted lanternfly feeding on grapevine yield and wine and juice quality.

This research group enclosed both red and white grapevines – Cabernet Franc and Chardonnay – in mesh cages in the field and infested them with between 20 and 350 spotted lanternflies per vine. We wanted to determine the effect of constant adult insect feeding on grapevine yield, fruit sugars and phenolics, which are chemical compounds that are important for wine color, flavor and aroma. We also wanted to know the density of infestation that would induce changes in yield and fruit and wine quality.

We found a decrease in sugar content in the fruit within a single season, as well as a decrease in phenolics in red wine. We also found a reduction in yield after the second year of consecutive insect feeding.

These findings suggest that, if not controlled, spotted lanternfly adult feeding could reduce income to growers by reducing yield and could affect the wine industry by reducing the quality of the drink.

How worried are Pennsylvania winemakers and how are they responding?

Perceptions vary depending on whether the winery or vineyard is in an area that has already been infested.

Those that have been dealing with lanternflies for a few years have established protocols for pest monitoring and applying insecticides. But those that haven’t experienced it yet are concerned about the insect’s arrival on their properties.

Owners of organic vineyards are also concerned, but there are few of those in this region.

Wineries are being affected by spotted lanternflies in at least two ways. First, for those that grow grapes, lanternflies have increased their costs due to the extra labor and insecticide applications needed to control them. Second, for wineries that are agrotourism sites, they need to keep outdoor seating spaces neat and free from lanternflies.

As an entomologist, what do you find most fascinating about these creatures?

Most insects that feed on plants lay their eggs close to a food source for the young to feed on when they hatch. But spotted lanternflies lay their eggs on almost anything – car tires, field equipment, rocks, fabrics, old wood, cardboard. This behavior facilitates the insect’s dispersal, as eggs can be easily transported without being noticed. Once the eggs hatch, the nymphs search for young plant shoots or herbaceous plants to eat.

Anything else people in Pennsylvania should know as they see lanternflies again this summer?

I think it’s important for the public to know that, as pretty as some of us may find spotted lanternflies, these insects are invasive, damaging and affecting the state economy. Everybody can help stop the spread of these insects by killing and avoiding transporting them at any living stage.

Spotted lanternflies lay eggs in masses. These masses look like light grayish-brown, mudlike or puttylike patches, typically about an inch long, and they are found on various surfaces. At any life stage the insects can be killed by squishing them, immersing them in hand sanitizer or freezing them for several days.

Read more of our stories about Philadelphia and Pennsylvania.

Flor Acevedo has received funding for her research from the USDA Crop Protection and Pest Management program (2023-70006-40597), the Pennsylvania Department of Agriculture, the Pennsylvania Wine Marketing and Research Board, the New York Wine and Grape Foundation, the Penn State University College of Agriculture, and the John H. and Timothy R. Crouch Endowment Grant for Viticulture, Enology, and Pomology Research.

– ref. Spotted lanternflies love grapevines, and that’s bad for Pennsylvania’s wine industry – https://theconversation.com/spotted-lanternflies-love-grapevines-and-thats-bad-for-pennsylvanias-wine-industry-260374

Source: The Conversation – USA (2) – By Nathan Meyers, Ph.D. candidate in sociology (September 2025 degree conferral), UMass Amherst

America has never been richer. But the gains are so lopsided that the top 10% controls 69% of all wealth in the country, while the bottom half controls just 3%. Meanwhile, surging corporate profits have mostly benefited investors, not the broader public.

This divide is expected to widen after President Donald Trump’s sweeping new spending bill drastically cuts Medicaid and food aid, programs that stabilize the economy and subsidize low-wage employers.

Moreover, the tax cuts at the heart of the bill will deliver tens of billions of dollars in benefits to the wealthiest households while disproportionately burdening low-income households, according to analyses by the nonpartisan Congressional Budget Office and Joint Committee on Taxation. By 2033, the bottom 20% will pay more in taxes while the top 0.1% receive $43 billion in cuts.

I am a sociologist who studies economic inequality, and my research demonstrates that the class-based inequalities exacerbated by the Trump bill are not new. Rather, they are part of a 50-year trend linked to social cleavages, political corruption and a declining belief in the common good.

The roots of class-based inequality

The decades following World War II were broadly prosperous, but conditions began changing in the 1970s. Class inequality has increased enormously since then, according to government data, while income inequality has risen for five decades at the expense of workers.

Economists usually gauge a country’s economic health by looking at its gross domestic product as measured through total spending on everything from groceries to patents.

But another way to view GDP is by looking at whether the money goes to workers or business owners. This second method – the income approach – offers a clearer picture of who really benefits from economic growth.

The money that goes to labor’s share of GDP, or workers, is represented by employee compensation, including wages, salaries and benefits. The money left over for businesses after paying for work and materials is called gross operating surplus, or business surplus.

The share of GDP going to workers rose 12% from 1947 to 1970, then fell 14% between 1970 and 2023. The opposite happened with the business surplus, falling 18% in the early postwar decades before jumping 34% from 1970 to today.

Meanwhile, corporate profits have outpaced economic growth by 193% since 1970. Within profits, shareholder dividends as a share of GDP grew 274%.

As of 2023, labor had lost all of the economic gains made since 1947. Had workers kept their 1970 share of GDP, they would have earned $1.7 trillion more in 2023 alone. And no legislation or federal action since 1970 has reversed this half-century trend.

When more of the economy goes to businesses instead of workers, that poses serious social problems. My research focuses on three that threaten democracy.

1. Fraying social bonds and livelihoods

Not just an issue of income and assets, growing class inequality represents the fraying of American society.

For instance, inequality and the resulting hardship are linked to worse health outcomes. Americans die younger than their peers in other rich countries, and U.S. life expectancy has decreased, especially among the poor.

Moreover, economic struggles contribute to mental health issues, deaths of despair and profound problems such as addiction, including tobacco, alcohol and opioid abuse.

Inequality can disrupt families. Kids who experience the stresses of poverty can develop neurological and emotional problems, putting them at risk for drug use as adults. On the other hand, when minimum wages increase and people begin saving wealth, divorce risk falls.

Research shows inequality has many other negative consequences, from reduced social mobility to lower social trust and even higher homicide rates.

Together, these broad social consequences are linked to misery, political discontent and normlessness.

2. Increasing corruption in politics

Inequality is rising in the U.S. largely because business elites are exercising more influence over policy outcomes, research shows. My related work on privatization explains how 50 years of outsourcing public functions – through contracting, disinvestment and job cuts – threatens democratic accountability.

Research across different countries has repeatedly found that higher income inequality increases political corruption. It does so by undermining trust in government and institutions, and enabling elites to dominate policymaking while weakening public oversight.

Since 2010, weakened campaign finance laws driven by monied interests have sharply increased corruption risks. The Supreme Court ruled then in Citizens United to lift campaign finance restrictions, enabling unlimited political spending. It reached an apex in 2024, when Elon Musk spent $200 million to elect Trump before later installing his Starlink equipment onto Federal Aviation Administration systems in a reported takeover of a $2.4 billion contract with Verizon.

Research shows that a large majority of Americans believe that the economy is rigged, suggesting everyday people sense the link between inequality and corruption.

3. Undermining belief in the common good

National aspirations have emphasized the common good since America’s founding. The Declaration of Independence lists the king’s first offense as undermining the “public good” by subverting the rule of law. The Constitution’s preamble commits the government to promoting the general welfare and shared well-being.

But higher inequality historically means the common good goes overlooked, according to research. Meanwhile, work has become more precarious, less unionized, more segmented and less geographically stable. Artificial intelligence may worsen these trends.

This tends to coincide with a drop in voting and other forms of civic engagement.

The government has fewer mechanisms for protecting community when rising inequality is paired with lower taxes for the wealthy and reduced public resources. My research finds that public sector unions especially bolster civic engagement in this environment.

Given increasing workplace and social isolation, America’s loneliness epidemic is unsurprising, especially for low earners.

All of these factors and their contribution to alienation can foster authoritarian beliefs and individualism. When people become cold and distrustful of one another, the notion of the common good collapses.

Inequality as a policy outcome

News coverage of the Trump bill and policy debate have largely centered on immediate gains and losses. But zoomed out, a clearer picture emerges of the long-term dismantling of foundations that once supported broad economic security. That, in turn, has enabled democratic decline.

As labor’s share of the economy declined, so too did the institutional trust and shared social values that underpin democratic life. Among the many consequences are the political discontent and disillusionment shaping our current moment.

Republicans hold both chambers of Congress through 2026, making significant policy changes unlikely in the short term. Democrats opposed the bill but are out of power. And their coalition is divided between a centrist establishment and an insurgent progressive wing with diverging priorities in addressing inequality.

Yet democratic decline and inequality are not inevitable. If restoring broad prosperity and social stability are the goals, they may require revisiting the New Deal-style policies that produced labor’s peak economic share of 59% of GDP in 1970.

Nathan Meyers does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.

– ref. Inequality has risen from 1970 to Trump − that has 3 hidden costs that undermine democracy – https://theconversation.com/inequality-has-risen-from-1970-to-trump-that-has-3-hidden-costs-that-undermine-democracy-259104

Source: The Conversation – USA (2) – By Karen Tan, Assistant Professor of Tourism and Hospitality Management, Middle Tennessee State University

“My dedication was questioned.”

“Managers or upper management have looked down upon taking time off.”

“People think that maybe you’re not as invested in the job, that you’re shirking your duties or something.”

These are just a few of the responses to questions I asked during a study I conducted on vacation guilt among American workers.

More than 88% of full-time, private sector workers in the U.S. receive paid time off. This benefit is ostensibly in place to improve employee morale and well-being.

Yet a 2024 Pew Research Center survey found that nearly half of American workers don’t take all the vacation days they’ve been allotted. And many of them feel as if they’re discouraged from using their time off. Ironically, what’s supposed to be a source of relaxation and restoration morphs into a stressor: As vacations approach, feelings of doubt and guilt creep in.

I’m from Singapore. Upon moving to the U.S. in 2016, I was surprised at how pervasive vacation guilt appeared to be.

Compared with many of the other countries where I’ve lived or worked, American culture seems to prioritize mental health and wellness. I assumed these attitudes extended to the American workplace.

Surprisingly, though, I noticed that many of my American friends felt guilty about taking time off that they’d earned. So as a scholar of tourism and hospitality, I wanted to understand how and why this happened.

Vacation guilt

To carry out the study, I collaborated with tourism scholar Robert Li. We interviewed 15 workers who had experienced feelings of guilt over taking time off. We also administered an online survey to 860 full-time employees who received paid time off from their employers.

We wanted to know whether employees felt less respected or believed that their bosses and colleagues saw them in a worse light for taking time off. Maybe they feared being seen as slackers or, worse, replaceable.

We found that 1 in 5 respondents to our survey experienced vacation guilt, and these concerns made them think twice about following through with their vacation plans. For those who eventually did take a vacation, they often tried to ease their guilt by going for fewer days. They might also apologize for taking a vacation or avoid talking about their vacation plans at work.

Some of the people we interviewed had pushed through their hesitation and taken their vacation as planned. Yet all of these employees believed that they’d been penalized for taking time off and that it led to poor performance reviews, despite the fact that their paid vacation days had been a clearly articulated, earned benefit.

The US is an outlier

The U.S. is the only advanced economy that doesn’t legally mandate a minimum number of vacation days. On top of that, only a handful of states require workers to be compensated for their unused vacation days.

Meanwhile, the law in other advanced economies entitles employees to a minimum amount of annual paid leave. The EU, for example, mandates at least 20 days per year on top of paid public holidays, such as Christmas and New Year’s Day, with a number of EU member countries requiring more than 20 days of paid vacation for full-time employees. Even in Japan, which is notorious for its workaholic culture, employees are entitled to a minimum of 10 days of paid leave every year.

Throughout much of the U.S., whether paid vacation time is offered at all depends on an employer’s generosity, while many employees face a “use-it-or-lose-it” situation, meaning unused vacation days don’t roll over from one year to the next.

Of course, not all workers experience vacation guilt. Nonetheless, the guilt that so many workers do feel may be symbolic of broader issues: an unhealthy workplace culture, a toxic boss or a weak social safety net.

For paid time off to serve its purpose, I think employers need to provide more than vacation days. They also need to have a supportive culture that readily encourages employees to use this benefit without having to worry about repercussions.

The journal publication on which this article was based was supported by the inaugural Seed Funding Forum, Fox
School of Business, Temple University, USA.

– ref. Why do so many American workers feel guilty about taking the vacation they’ve earned? – https://theconversation.com/why-do-so-many-american-workers-feel-guilty-about-taking-the-vacation-theyve-earned-254913